<?php

/**
 * source: http://www.white-hat-web-design.co.uk/articles/php-image-resizing.php
 * with additional comments
 */

class CustomImage {

   var $image;
   var $image_type;

   function CustomImage($filename) {
       $this->load($filename);
   }

   function load($filename) {
      $image_info = getimagesize($filename);
      $this->image_type = $image_info[2];
      
      try {
        if( $this->image_type == IMAGETYPE_JPEG ) {
             $this->image = @imagecreatefromjpeg($filename);
          } elseif( $this->image_type == IMAGETYPE_GIF ) {
             $this->image = @imagecreatefromgif($filename);
          } elseif( $this->image_type == IMAGETYPE_PNG ) {
             $this->image = @imagecreatefrompng($filename);
          }
      } catch (Exception $e) {
          sfContext::getInstance()->getLogger()->debug('load custom image: ' . $php_errormsg);
          sfContext::getInstance()->getLogger()->debug('load custom image: '. $e->getTraceAsString());
      }
      
   }

   function save($filename, $image_type=IMAGETYPE_JPEG, $compression=75, $permissions=null) {
      if( $image_type == IMAGETYPE_JPEG ) {
         imagejpeg($this->image,$filename,$compression);
      } elseif( $image_type == IMAGETYPE_GIF ) {
         imagegif($this->image,$filename);
      } elseif( $image_type == IMAGETYPE_PNG ) {
         imagepng($this->image,$filename);
      }
      if( $permissions != null) {
         chmod($filename,$permissions);
      }
   }

   function output($image_type=IMAGETYPE_JPEG) {
      if( $image_type == IMAGETYPE_JPEG ) {
         imagejpeg($this->image);
      } elseif( $image_type == IMAGETYPE_GIF ) {
         imagegif($this->image);
      } elseif( $image_type == IMAGETYPE_PNG ) {
         imagepng($this->image);
      }
   }

   function getWidth() {
      return imagesx($this->image);
   }
   
   function getHeight() {
      return imagesy($this->image);
   }

   /**
    * If you want to resize to a specifed height but keep the dimensions ratio
    * @param int    pixel $height
    */
   function resizeToHeight($height) {
      $ratio = $height / $this->getHeight();
      $width = $this->getWidth() * $ratio;
      $this->resize($width,$height);
   }

   /**
    * If you want to resize to a specifed width but keep the dimensions ratio
    * @param int    pixel $width
    */
   function resizeToWidth($width) {
      $ratio = $width / $this->getWidth();
      $height = $this->getheight() * $ratio;
      $this->resize($width,$height);
   }

   /**
    *
    * @param int or float   percentage $scale
    */
   function scale($scale) {
      $width = $this->getWidth() * $scale/100;
      $height = $this->getheight() * $scale/100;
      $this->resize($width,$height);
   }

   /**
    * Resize the image to a specified height and width
    * @param int    pixel $width
    * @param int    pixel $height
    */
   function resize($width,$height) {
      $new_image = imagecreatetruecolor($width, $height);
      imagecopyresampled($new_image, $this->image, 0, 0, 0, 0, $width, $height, $this->getWidth(), $this->getHeight());
      $this->image = $new_image;
   }
}

?>
